The present invention relates generally to an electronic apparatus, and more particularly to a housing structure of the electronic apparatus. The electronic apparatus conceptually covers a laptop or notebook-type personal computer (“PC”), a personal digital assistant (“PDA”), an electronic dictionary, electronic stationery, and a game machine. The present invention is suitable, for example, for a housing structure of a laptop PC.
The recent laptop PC has been increasingly required to improve the environmental performance, such as recyclability, disassembly easiness, in addition to simple miniaturization and highly functional performance. Therefore, the housing material of the laptop PC is required to have high recyclability and disassembly easiness through the smaller number of components and a simple structure. In addition, it is necessary to easily access a maintenance requiring component, i.e., not by completely disassembling the housing but by partially disassembling it.
A typical housing for the laptop PC is made by resin molding and secures a size precision for highly functional performance. The typical housing has a display section mounted with an LCD screen, and a body section to which the display section is foldably and unfoldably connected. The body section has a housing structure including a lower cover, an upper cover (or palm rest) screwed onto the lower cover, and a keyboard.
The body section screws, onto the lower cover, a circuit board mounted with a CPU and a chip set, and various drivers connected to the circuit board, such as a CD/DVD drive, a hard disc drive (“HDD”), and a floppy disc drive (“FDD”). The body section has a metal plate on the rear surfaces of the upper and lower covers for electromagnetic shield.
Prior art include, for example, Japanese Patent Applications, Publication Nos. 2001-5567 and 2000-26534.
The conventional laptop PC does not exhibit sufficient environmental performance.
Initially, resin has several disadvantages: Firstly, resin's energy efficiency is low during molding and recycling, and resin generates hazardous substances, such as dioxin during burning. Secondly, resin has low durability and is likely to crack or chip. Thirdly, resin has a low heat radiation characteristic, enclosing the heat in the housing and thermally damage the PC. Accordingly, use of a metallic material and press molding is proposed instead of resin molding, but causes deteriorated dimension accuracy, wastes a material, and increases the cost. The metallic molding consumes much energy during a production of a mold and during molding, and increases the cost. Fourthly, resin is so weak that it needs reinforcement with a rib, etc., making a shape complicated, and deteriorating the disassembly easiness and maintainability.
Next, the metal plate for electromagnetic shield increases the number of components.
Moreover, the screw assembly requires unscrewing of all screws, making the disassembly arduous and lowering the maintainability. For example, disadvantages occur, such as a complex structure and the increased number of components, because it is necessary to unscrew the lower cover from the circuit board or to provide an inspection hatch in order to maintain the circuit board or the electronic components on the board.